GoldfinderG2 (knock off Teknetics G2)assembly/disasembly/taking apart

[nonkapo]

Here you'll find info how to take apart Goldfinder G2 (aka Teknetics G2 chinese knock off). I hope i post it in the proper thread.

ATTENTION, VERY IMPORTANT!!!
If you do this your waranty will void. The author do not bear any responsibility if you do something wrong, hurt your self or damage your equipment when you follow the instructions. You do this at your own risk. If you have no experience please go to the otorized workshop or technician.

1. Remove the potentiometer's knobs by pulling them towards you. You can carefully use fork to do that trying to not damage the switch foil below.

2. After disataching the coil you must unscrew three Philips head screws (1,2,3) and the back side cover will get open. If you need the control box dis-attached, pull down the foam cover of the handle and remove hidden screw number 4. If you need the handle to be removed continue with hidden screws 5,6 and bolts 7 & 8. If you need elbow support removal go for bolt 9.

[nonkapo]

3. The assembly is reverse of the disassembly. Following photos of the board, chips and critical connections. Note that the soldering is made with those parts of the body where sunshine do not reach . The cables used are very thin and get cut easily. Still on G2 they are better than on the T2 which if not mistaken is the higher end product. Cable description is missing but at least almost everywhere there is a color code silkscreen on the board.

Hope this will be helpful to one who like to compare the original product with the counterfeit and in cases of repairs.
Enjoy.

[SVEN1]

I see they marked the board GoldFinder instead of Fisher or Teknetics like most were labeled. On the clones the parts are not centered properly when soldered and soldering overall not as good as the genuine product.

[nonkapo]

Yes,the quality is below average.
Here some updated photos of the chips and their description:

PIC16F946 i/PT - 64-Pin Flash-Based, 8-Bit CMOS Microcontrollers with LCD Driver and nanoWatt Technology;


PIC16F886 i/SO - 28-Pin, Enhanced Flash-Based 8-BitCMOS Microcontrollers with nanoWatt Technology;

ADS1246 - 24-Bit, 2kSPS, 1-Ch Delta-Sigma ADC With PGA for Precision Sensor Measurement;

SN74HC393 - Dual 4-bit binary counters;

TLE2426 - Rail splitter precision virtual ground;

LP2950 - Adjustable micropower voltage regulator

[Skippy]

Interesting stuff.
If you're putting idents of the IC's up, could you please do all of them? The IC's are all labelled Uxx , there's several opamps / analogue switches you've missed.

[nonkapo]

Noted, my bad. However here I'll need some help. Never deal with smd components much.
U8,9,10 - JC5R - probably 10 ohm single-pole double-throw analog switch?!?!? Correct me if i'm wrong please.
U6,7- C20A - probably LMV7239 ultra low power,low voltage 75ns comparators ?!?!? Correct me if i'm wrong please.
Seems there are no opamps?

P.S. - there is one hiding from me behind the pot- LTAFJ - LT6230 low noise, rail-to-rail output unity-gain stable op amp???? Right?

[Skippy]

Thanks.
The LTAFJ is the standard first-stage pre-amp in most top Fisher/Tek machines, including T2, F75. There 'lower' machines use the LTAFL, which is the LT6233, a bit noisier.

[nonkapo]

You welcome. Are these two pin compatible/plug&play(mean ltafj/ltafl)??? Hope i do not miss something else. Oooops on the T2 thread for sure:-(. Do not like to open it again buuut no choice;-). Some are covered by flux.

[bernte_one]

can find more photos on entry postings
http://www.geotech1.com/forums/showt...ght=goldfinder

[nonkapo]

Thanks,bernte, very useful. For me it is still worth to go for the original or aftermarket coil, as i get the detectors free. Also i can try DIY, however, it is not simple monoloop for PI .

[nonkapo]

Well, i receive the 5inch original teknetics coil and... it works like beast. It ground balances properly now and is kinda good on small jewelry. Unfortunately my 5x10 will arrive only after 26, so i can update you with test and possibly video.

[nonkapo]

Some treasures

Some finds buried around 20cm in the sand. Do not get overexcited - it's all silver plated aluminum and steel, but that does not make it less fun to be discovered;-). As usual the amount of steel wire, nails, foil, valve needless, coke cans etc is accounting to 90 percent of the discoveries, as i'm not using discrimination.

[nonkapo]

The pics below shows by far some of the smallest items i found and the first ever jewelry. I'm not sure whether these are from precious metals. The pneumatic gun bullet is as per what i know lead. The jewelry have no markings, accept the smallearing which bears the Swarowski swan. Looking for trusted jeweler who can give me reliable information.